Download Bel Canto Design SET 40 User`s guide

Bel Canto Design
PHONO 1
Low Noise Solid State Phono Preamplifier
User's Guide and
Operating Information
Bel Canto Design • 212 Third Avenue North – Suite 345 • Minneapolis, MN
55401
Phone: (612) 317.4550 • Fax: (612) 359.9358 • Email: [email protected] Aug.2000
Low Noise Solid State Phono1 Preamplifier
The Bel Canto Design’s PHONO1 components are selected for high sound quality,
precision, technical virtue, and material quality. Bel Canto’s circuit designs and component
quality will provide superb performance and years of listening satisfaction.
Page 2
PHONO Owner's Manual
Bel Canto Design grew from the quest to achieve the ultimate
musical satisfaction from an audio system. This quest began with the discovery of
the inherent sonic qualities and musical performance potential of a nearly
forgotten technology, the single-ended triode amplifier. The ability of this type of
amplifier to recreate the musical experience and evoke a powerful emotional
response in the listener, much like the live event, inspired the development of the
SET line of amplifiers through the ultimate expression of this technology. The
SET circuit was developed for use as both a cornerstone for a modern audio
system and as a reference tool to explore the reasons behind the single-ended
triode amplifier's uniquely musical attributes.
For more than ten years this effort has continued and the
result is a unique line of fine audio amplifiers and preamplifier that are designed
to embody the unparalleled musical reproduction of the single-ended triode
architecture. Bel Canto Design's goal simply to provide the most expressive and
powerful musical experience outside of the live event and bring some of the
greatest musicians and their performances into the intimacy of your home.
Bel Canto Design
PHONO Owner's Manual
Page 3
Design Features
A classic architecture had been chosen to
provide a firm foundation for the RIAA
equalization and gain stages of the Phono1.
The RIAA uses a robust series EQ architecture
with high precision, low noise, high linearity
resistors and high precision polypropylene film
and foil construction capacitors for optimum
signal transfer. The Moving Magnet gain is in the
RIAA Equalization stage, using the latest ultra
low distortion, low noise monolithic preamplifier
device. This device combines extremely low
distortion with low offset, noise and high output
drive capability to be a transparent conduit for
the musical signal. The high performance gain
and equalization setting RC elements dominate
the musical signature of this MM/EQ stage,
leading to a detailed yet musical presentation.
The MM/EQ stage provides 40 dB of 1kHz gain.
The MC gain stage is connected optionally
before the MM/EQ stage and provides extremely
low noise and low distortion, again using high
performance resistors for gain setting and
adjustable input loading. The MC stage is
connected into the circuit using gas tight gold
jumpers, these jumpers also are used to set the
MC stage gain at 14 or 20 dB. This provides up
to 60 dB of 1 kHz gain for use with low output
MC cartridges.
The first stage of filtering drives eight (4)
individual regulators providing power
to the analog circuits, where audio grade
electrolytic and film bypass capacitors
complement the active regulation stages. A
highly isolated power transformer, oversized by
10X provides extremely low-noise and robust
raw power to feed the precision regulators.
The input impedance, gain and relative noise
levels can be optimized for virtually any
cartridge available. This is achieved through the
use of gas tight gold jumpers and precision
miniature switches to simplify the optimization
for virtually any cartridge.
The elegant simplicity of the signal path allows
the Phono1 to preserve the entire audio signal.
Warm Up
The Phono1's sonic performance will start to
stabilize after approximately forty (40) hours of
continuous power up.
No coupling capacitors are used in the signal
path, removing this source of signal
degradation. A servo is used around the MM/EQ
stage to insure low DC offset for direct coupling
to the control preamplifier.
There is over 10,000 uf of capacitance and LC
high frequency filters providing the raw DC.
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PHONO Owner's Manual
Unpacking
Unpacking
dealer or Bel Canto Design.
The box containing your Phono1 contains the
following parts:
Save all packing materials as the packing is
specially designed to protect the preamplifier for
shipping or transporting it. If you lose or
damage the packing materials or carton, please
contact your dealer or distributor before
attempting to transport the preamplifier.
1 - Phono1 User's Guide
1 - Power Cable for connection to utility
power [1.85m, 6' long] (External Box
Version Only)
1 – Phono1 preamplifier
1 - Owner's Warranty / Registration Sheet
Carefully your new unit and check for shipping
damage. If there is any damage, or if any piece
is missing, please contact your
The Phono1's power supply is preset for
the proper national voltages before you r
eceive it. The power cable (External Unit
Only) will have the proper plug for your
local power system. If you believe this is
not true, please contact your dealer
immediately. Do not attempt to alter or
change power settings yourself!
Warning
Do not connect power to this preamplifier yet!
This preamplifier, like any electrical component, can be dangerous and cause injury unless cor
rect handling procedures are observed and used. Before powering this preamplifier it is
necessary to read and follow proper procedures concerning its setup and use.
Any tampering of internal parts, other than for Moving Coil / Moving Magnet (MM/MC) setup, will
immediately void your warranty.
For Warranty Coverage complete and mail the Owner's Registration Papers
immediately.
PHONO Owner's Manual
Page 5
Gain Settings, Initial Setup, and Placement
• Gain Settings
Internal jumpers accommodate Moving
Magnet, Moving Coil (Low Gain), and Moving Coil
(High Gain) settings. The Phono1 is shipped
from the factory set for Moving Magnet
operation. Gain structure changes are easily
made by first removing the two gold nuts from
the RCA output jacks using a 5/8” socket. Take
care not to scratch the chassis by avoiding
contact between the socket and the end panel.
Next, remove the four stainless steel screws
securing the opposite end panel with a 7/64”
Allen tool. Carefully slide the circuit board partly
out by slowly pulling on the input side end panel
while securely holding the chassis. The circuit
board only needs to be slid out part way to gain
access to the internal jumpers. There are a total
of 6 blue jumpers, which are labeled on the
circuit board in the following locations: J7, J4,
J6, J11, J3, and J5. They are easily removed by
pulling them off of the 2-pin headers. When
replacing the jumpers, be sure the jumper is
oriented with the characters ‘3M’ at the top,
otherwise the jumper may not function.
MOVING MAGNET CARTRIDGE
When using a Moving Magnet cartridge, the
jumpers in locations J4, J6, J3, and J5 need to
be placed in the positions labeled ‘MM’ (40dB of
gain at 1kHz). The two remaining jumpers in
locations J7 and J11 are inactive with this
setting, and their positions are therefore
irrelevant.
MOVING COIL CARTRIDGE
When using a Moving Coil cartridge, the
jumpers in locations J4, J6, J3, and J5 need to
be placed in the positions labeled ‘MC’. If low
gain (54dB at 1 kHz) is desired, place the
jumpers in locations J2 and J11 in the positions
labeled ‘LOW’. If high gain (60dB at 1 kHz) is
desired, place the jumpers in locations J2 and
J11 in the positions labeled ‘HIGH’.
Bel Canto recommends that you consult your
turntable consultant / dealer to ascertain the
exact setting to use with your particular system.
Page 6
In the lack of specific system information the
following can be used as a guide:
- Use the Hi gain/MC setting when the output of
your cartridge has less than .5mv output.
- Use the Low gain/MC setting when your
cartridge has more than .5mv output.
When set for Moving Coil, the externally
accessible loading DIP switches located
between the input jacks are active. Loading
options range from 50 Ohms to 50K Ohms, and
right and left channels are adjustable
independently.
• Cartridge Loading
Cartridge loading settings should directly
correspond to the cartridge manufacturers
recommended loading figure. If you don’t know
the recommended loading of your cartridge,
please contact the manufacturer or your dealer
for this information.
Loading settings can be done using the DIP
switches seen through the opening near the
RCA inputs of your phono stage. For the normal
settings seen on the panel below the DIP switch
opening use a pen or small pointed object to
switch down the corresponding DIP switch. All
other switches should be in the up position.
Note: Changes to the DIP switch
positions only apply when the MM/MC
jumpers, located inside the Phono1, are
in the Moving Coil (MC) position.
Please refer to the following chart for a
complete listing of loading settings
possible to correctly match your
cartridge:
PHONO Owner's Manual
DIP switch setting
BLANK = UP, X = DOWN
Cartridge 50 100 500 1 k 10 k
Load(ohms)
50000
x
8333
x
980
x
x
893
x
495
x
x
472
x
x
331
x
x
x
321
x
100
x
x
99
x
x
91
x
x
x
90
x
x
83
x
x
x
77
x
x
x
x
76
50 x
x
48 x
x
x
47 x
x
45 x
x
x
43 x
x
33 x
x
x
32 x
x
x
31 x
x
x
x
30 x
• RCA Main Output Jacks for Left and
Right Channels
These connectors are found on the
opposite side as the RCA inputs, ground
connector, and loading switches. The Phono1
has one pair of RCA type outputs, which can be
run into any input of any preamplifier with RCA
type connectors. Do not run the output of your
Phono1 into the phono input of another
preamplifier. In this case you can use any RCA
auxiliary input rather than the phono input.
• Phono1 Placement
The Phono1 may be situated within your
system in any convenient manner desired. The
most typical arrangement places the Phono1
near or behind the turntable in order to make the
shortest possible connection between the
tonearm output and phono stage input. By
eliminating as much tonearm interconnect wire
as possible you will reduce the system’s
susceptibility to RF interference and sonic
impact of long wires.
It is recommended to use a high quality type
stand or isolation platform capable of dissipating
/ isolating vibration and resonance.
• Input Panel Connections
The input connection panel includes one pair
of RCA type inputs to be used for connection of
your tone-arm wires from your turntable.
Ground connection is located on the input
panel should only be used if necessary. You
should first try to hook up your turntable without
the use of this grounding plug. In the case that
hum is heard through your speakers when the
Phono1 is connected, you can easily ground
your turntable by connecting the turntable
ground to the input panel ground terminal. If
grounding your turntable does not alleviate the
hum problems, please contact your dealer for
further information specific to your system
setup.
PHONO Owner's Manual
Page 7
Specifications
RIAA accuracy Into >20K Ohms • 20 Hz-20 kHz +/- 0.25 dB
Signal to Noise Ratio • > 75 dB A weighted MM/MC
Distortion at 3 Volts RMS out • <0.01%
Input configuration and impedance • Adjustable /MC, 47 Kohms/MM
Output Options • 1 Pair RCA
Output Impedance • 50 ohms
Maximum Output Level • 9Vrms
1 kHz Gain • 40, 54 or 60 dB
Power Requirements • 115/230 VAC; 50-60 Hz 10 watts
Size • 3.6 x3.6 x 9 inches
Weight • 3.5 lbs
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PHONO Owner's Manual